My Logitech Revolution doesn't have the screws under the mouse pads --

My MX Revolution doesn’t have the screws under teh mouse pads — How do I open to clean.

Can’t read the PID on the mouse suspect P/N 831735-0000. Definitely a DZL-M-RBQ124

CMII ID: 2006DJ1580. Has the original USB dongle, not the Universal from the later models: PID of Dongle is LZ64784 with a part # 831735-1000